A230490 - cp's OEIS frontend

A230490 Size of largest subset of [1..n] containing no three terms in a geometric progression with integer ratio.

n	a(n)
1	1
2	2
3	3
4	3
5	4
6	5
7	6
8	7
9	7
10	8
11	9
12	10
13	11
14	12
15	13
16	14
17	15
18	15
19	16
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	23
29	24
30	25
31	26
32	26
33	27
34	28
35	29
36	30
37	31
38	32
39	33
40	33
41	34
42	35
43	36
44	36
45	37
46	38
47	39
48	39
49	40
50	41
51	42
52	42
53	43
54	44
55	45
56	46
57	47
58	48
59	49
60	50
61	51
62	52
63	52
64	52
65	53
66	54
67	55
68	55
69	56
70	57
71	58
72	59
73	60
74	61
75	62
76	62
77	63
78	64
79	65
80	65
81	66
82	67
83	68
84	69
85	70
86	71
87	72
88	73
89	74
90	75
91	76
92	76
93	77
94	78
95	79
96	79
97	80
98	81
99	81
100	81

[1, 2, 3, 3, 4, 5, 6, 7, 7, 8, 9, 10, 11, 12, 13, 14, 15, 15, 16, 16, 17, 18, 19, 20, 21, 22, 23, 23, 24, 25, 26, 26, 27, 28, 29, 30, 31, 32, 33, 33, 34, 35, 36, 36, 37, 38, 39, 39, 40, 41, 42, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 52, 52, 53, 54, 55, 55, 56, 57, 58, 59, 60, 61, 62, 62, 63, 64, 65, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 76, 77, 78, 79, 79, 80, 81, 81, 81]

cp's OEIS Frontend

A230490 Size of largest subset of [1..n] containing no three terms in a geometric progression with integer ratio.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	3
5	4
6	5
7	6
8	7
9	7
10	8
11	9
12	10
13	11
14	12
15	13
16	14
17	15
18	15
19	16
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	23
29	24
30	25
31	26
32	26
33	27
34	28
35	29
36	30
37	31
38	32
39	33
40	33
41	34
42	35
43	36
44	36
45	37
46	38
47	39
48	39
49	40
50	41
51	42
52	42
53	43
54	44
55	45
56	46
57	47
58	48
59	49
60	50
61	51
62	52
63	52
64	52
65	53
66	54
67	55
68	55
69	56
70	57
71	58
72	59
73	60
74	61
75	62
76	62
77	63
78	64
79	65
80	65
81	66
82	67
83	68
84	69
85	70
86	71
87	72
88	73
89	74
90	75
91	76
92	76
93	77
94	78
95	79
96	79
97	80
98	81
99	81
100	81

n	a(n)
1	1
2	2
3	3
4	3
5	4
6	5
7	6
8	7
9	7
10	8
11	9
12	10
13	11
14	12
15	13
16	14
17	15
18	15
19	16
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	23
29	24
30	25
31	26
32	26
33	27
34	28
35	29
36	30
37	31
38	32
39	33
40	33
41	34
42	35
43	36
44	36
45	37
46	38
47	39
48	39
49	40
50	41
51	42
52	42
53	43
54	44
55	45
56	46
57	47
58	48
59	49
60	50
61	51
62	52
63	52
64	52
65	53
66	54
67	55
68	55
69	56
70	57
71	58
72	59
73	60
74	61
75	62
76	62
77	63
78	64
79	65
80	65
81	66
82	67
83	68
84	69
85	70
86	71
87	72
88	73
89	74
90	75
91	76
92	76
93	77
94	78
95	79
96	79
97	80
98	81
99	81
100	81

n	a(n)
1	1
2	2
3	3
4	3
5	4
6	5
7	6
8	7
9	7
10	8
11	9
12	10
13	11
14	12
15	13
16	14
17	15
18	15
19	16
20	16
21	17
22	18
23	19
24	20
25	21
26	22
27	23
28	23
29	24
30	25
31	26
32	26
33	27
34	28
35	29
36	30
37	31
38	32
39	33
40	33
41	34
42	35
43	36
44	36
45	37
46	38
47	39
48	39
49	40
50	41
51	42
52	42
53	43
54	44
55	45
56	46
57	47
58	48
59	49
60	50
61	51
62	52
63	52
64	52
65	53
66	54
67	55
68	55
69	56
70	57
71	58
72	59
73	60
74	61
75	62
76	62
77	63
78	64
79	65
80	65
81	66
82	67
83	68
84	69
85	70
86	71
87	72
88	73
89	74
90	75
91	76
92	76
93	77
94	78
95	79
96	79
97	80
98	81
99	81
100	81